Especially devices with a very high current load often do not provide the possibility for separating the corresponding control and/or power electronics from the power source in case of a thermal fault, i.e. for example when very high ambient temperatures, which are significantly above 100 EC, occur as a result of middle- or low-resistance short circuits. Appropriate temperature fuses for preventing thermal damages are, however, necessary in particular in motor vehicles.
It is, for example, known from the U.S. Pat. No. 6,737,770 B2 how to separate the coil of a brushless motor from the power source by means of a fuse. In so doing, an end of the fuse is soldered on; so that when a certain limit temperature is exceeded, the mechanically biased part of the fuse leads to a separation of the soldered joint.
In the European patent EP 1 120 888 A1, a heat-resisting mechanism is disclosed, which is thermally coupled to a heat sink of a circuit breaker and separates the power source of a brushless motor from the coil. As is the case in the U.S. Pat. No. 6,737,770 B2, an end of the fuse is also soldered on here. When a certain limit temperature is exceeded, the mechanically biased part of the fuse thus leads to a separation of the soldered joint. A corresponding fuse is furthermore known from the patent WO 00/08665.
The German patent DE 39 09 302 A1 reveals a fuse, in which a new alloy with a high electrical resistance arises from the melting of two highly electrically conductive alloys. Said new alloy prevents a further flow of high currents.
A disadvantage of the aforementioned fuses is, for example, the limited service life as a result of a permanently mechanically biased, soldered joint. Furthermore, insufficiently high tolerances can arise due to a simultaneous influence of temperature and current. A satisfactory and safe usage, in particular for the automotive field, is therefore basically not provided.